Kelley Blue Book names cars in every category that save fuel without sacrificing very much else.

Powered by an advanced diesel engine, the E320 Bluetec is as smooth and pleasant to drive as you'd expect from a Mercedes-Benz.

Unfortunately, due to ultra-strict emissions regulations in some states - among them California and New York - the E320 isn't for sale everywhere in the U.S. For now, it's available on a special two-year lease in California. That deal will be available in the other diesel-restricted states soon.